---
title: A2UI Atomic Catalog
description: 480 typed UI atoms an AI agent composes into real rendered interfaces instead of generating HTML.
canonical: https://a2uicatalog.ai/
---

# A2UI Atomic Catalog

480 typed UI atoms an AI agent composes into real rendered interfaces — web, Google Meet,
Apps Script, Google Chat and MCP Apps — instead of generating HTML.

## Start here

- [Browse the catalog](https://a2uicatalog.ai/) — search and preview every atom live
- [Developers](https://a2uicatalog.ai/developers/) — MCP + REST integration guide
- [OpenAPI specification](https://a2uicatalog.ai/openapi.json)
- [agents.md](https://a2uicatalog.ai/agents.md) — agent-facing how-to
- [MCP Apps playground](https://a2uicatalog.ai/surfaces/mcp-apps)

## What this is

An independent, unofficial, open-source project (MIT licensed). Not affiliated with, endorsed
by, or sponsored by Google or Anthropic. A2UI is Google's protocol; MCP is Anthropic's.

Source: https://github.com/a2uicatalog/a2ui
Maintained by Curtis Krygier — https://www.linkedin.com/in/curtiskrygier